Fix-#4867 provide positive test for fix

Author: landerlo

tests/pos/i4867.scala

@@ -0,0 +1,15 @@
+object Main_i4867 {
+
+  given extension [AB](ab: AB) {
+    def id: AB = ab
+  }
+
+  def main(args : Array[String]) : Unit = {
+    val int : Int = 2
+    val foundInt : Int = int.id
+
+    val stringOrInt : String | Int = 1
+    val foundAny : String | Int = stringOrInt.id
+  }
+
+}